.py

# BlenderユーザーのためのPython入門
# 第24節 複数のキューブをsinで並べてグラデーションする
import colorsys
import bpy
import math
import random
def delete_all():
    """既存のメッシュとマテリアルを削除します。"""
    for mesh in bpy.data.meshes:
        assert isinstance(mesh, bpy.types.Mesh)
        bpy.data.meshes.remove(mesh)
    for material in bpy.data.materials:
        assert isinstance(material, bpy.types.Material)
        bpy.data.materials.remove(material)
def make_sphere(x, y, z):
    """座標(x, y, z)に球を作成します。"""
    bpy.ops.mesh.primitive_ico_sphere_add(location=(x, y, z), radius=1.0)
    bpy.ops.object.material_slot_add()
    bpy.ops.object.shade_smooth()
    return bpy.context.active_object
def make_spheres(half):
    """2 * half + 1個の球を正弦波（または余弦波）の形に並べます。"""
    objects = []
    if random.random() >= 0.5:
        f = math.sin
    else:
        f = math.cos
    for x in range(-half, half + 1):
        z = f(math.radians(x * 10)) * 10
        object = make_sphere(x, 0, z)
        objects.append(object)
    return objects
def make_material(name, color):
    """与えられた名前と色のマテリアルを作ります。"""
    material = bpy.data.materials.new(name)
    material.diffuse_color = color
    material.use_nodes = True
    node_tree = material.node_tree
    assert isinstance(node_tree, bpy.types.ShaderNodeTree)
    principled_bsdf = node_tree.nodes['Principled BSDF']
    assert isinstance(principled_bsdf, bpy.types.ShaderNodeBsdfPrincipled)
    principled_bsdf.inputs['Base Color'].default_value = color
    return material
def make_materials(n):
    """n個のマテリアルを虹色状に作ります。"""
    materials = []
    for i in range(n):
        name = 'Color' + str(i)
        # [0, 1)の範囲で色相を遷移させます。
        (r, g, b) = colorsys.hsv_to_rgb(i / (n - 1), 1.0, 1.0)
        material = make_material(name, (r, g, b, 1.0))
        materials.append(material)
    return materials
def set_materials(objects, materials):
    """各メッシュに対応するマテリアルを割り当てます。"""
    for i in range(len(objects)):
        objects[i].material_slots[0].material = materials[i]
if __name__ == '__main__':
    delete_all()
    objects = make_spheres(18)
    materials = make_materials(len(objects))
    set_materials(objects, materials)